The Kawai & Teisco Analog Synths Group

Hi,

I'm new here so my post might be repetitive but bear with me just a 
minute;)

I have tiny experience working with Korgs; Polysix, Poly-61, Poly-
800. I know what a non-rechargeable lithium battery is, I know what a 
rechargeable Ni-Cad battery is, I know the modifications needed to 
install a lithium in place of an old Ni-Cad, I've resoldered these 
things many times, so I do have some insight as to these matters.

I bought my SX-240 in perfect condition - the original battery did 
not leak. But, being preventive, I decided to replace it with a new 
one. First I tried a Ni-Mh battery. Then I used a NiCad. Everytime 
the result was the same: after some days Kawai was losing its memory. 

Finally I opened it, connected the battery circuit to a volt-meter, 
and what I found was this: When I switch the synth on, the battery is 
being charged in a fashion that seems perfectly OK, reaching 3,6V. 
But the moment I switch the synth off, it starts to fall down very 
fast. From 3.6V to 3V in the first 30 seconds and then from 3V to 2V 
in the next couple of minutes. You know what's next...

What's the matter ? What is killing my batteries ?
And what battery should I use in the place of the original one? A 
NiMh or a NiCad ? Does anybody have the battery circuit diagram for 
SX240 ?


thanks 
aero